A supplier's promises only matter if they are backed by paper you can file and audit. This is the document checklist every buyer should run before signing a PO — and what each document actually proves.
1. Quality-System Certificates (Factory Level)
Ask for the certificate number, issuing body and expiry — a logo is not a certificate.
- ISO 9001 — baseline quality management. Verify the scope covers silicone molding, not just "trading".
- ISO 13485 — required for medical device components. Confirm the scope covers your part category.
- ISO 14001 / ISO 45001 — environmental and occupational health & safety management.
2. Material-Compliance Test Reports (Per Material)
These are material tests, not factory licenses — do not let a supplier imply an "FDA-certified factory". Request the actual report per material grade:
- FDA 21 CFR 177.2600 — US food-contact compliance.
- LFGB §30/31 — EU food-contact compliance.
- RoHS / REACH — restricted substances for electronics and EU markets.
- PFAS non-detect — increasingly required for US and EU consumer goods.
- ISO 10993 / USP Class VI — biocompatibility for medical applications.
3. First-Article Inspection (FAI) Report
An FAI verifies that the first production sample meets every drawing dimension before volume runs. Ask for the dimensional report against your CAD, with measured vs. nominal values — not just a "passed" stamp.
4. Cpk / Cp Process-Capability Data
For critical dimensions, request Cpk / Cp values. A Cpk ≥ 1.33 is the common target; a supplier who reports a lower value honestly (rather than hiding it) is a supplier you can trust.
Transparent process data is worth more than a perfect number that cannot be reproduced.
5. PPAP Documentation (Automotive & High-Reliability)
For automotive or high-reliability programs, request PPAP documentation — typically Level 3, including the design record, DFMEA/PFMEA, control plan, dimensional results and material certifications.
6. Per-Batch / Lot-Traceability Records
Ask how the supplier traces each shipment back to a master-batch lot. Per-batch test reports and a lot-retention log prove the supplier can stand behind every carton, not just the first sample.
Your Document Checklist at a Glance
| Document | What it proves | When to request |
|---|---|---|
| ISO 9001 / 13485 cert | Quality system, scope, issuer, expiry | Before shortlisting |
| FDA / LFGB / RoHS / PFAS | Material compliance per grade | Before sampling |
| FAI report | First article meets drawing | At first-article sign-off |
| Cpk / Cp data | Process repeatability | For critical dimensions |
| PPAP (Level 3) | Full production approval | Automotive / high-reliability |
| Per-batch / lot trace | Every carton is traceable | Every shipment |
See how CYES organizes these documents on our quality documents page — certificates, FAI and calibration samples, with real numbers available under NDA.